Search results for "River"
showing 10 items of 564 documents
Desalination. From a questioned resource to a necessary and strategic resource during drought situations for the water supply in the Segura River Bas…
2018
En España, la desalinización ha cobrado un gran impulso en las dos últimas décadas gracias a la aprobación en 2001 del Plan Hidrológico Nacional y en 2004 del Programa A.G.U.A. Ello ha sido motivado por dos factores principales: 1) Las recurrentes e intensas sequías en las últimas décadas, en especial, la de los años noventa en la que se puso de manifiesto la necesidad de la búsqueda de nuevas fuentes y la apuesta por los recursos hídricos no convencionales (desalinización y aguas regeneradas depuradas); y 2) Cambio del antiguo paradigma hidráulico basado en el incremento de la oferta mediante las transferencias de aguas. El objetivo de esta investigación es analizar el rol que ha desempeña…
Rivero Rodríguez, M. y Gaudin, G. (Coords.): "Que aya virrey en aquel reyno". Vencer la distancia en el imperio español
2020
Modeling risk perception in ATIS context through Fuzzy Logic
2011
Abstract This research is aimed at investigating the effect of accuracy of ATIS (Advanced Traveller Information Systems) in terms of route choices and travellers concordance to informative system. A Stated Preference Experiment has been made by using a Travel Simulator developed at the Technische Universiteit of Delft (The Netherlands). During the experiment respondents have been asked to make repeated route choices in presence of ATIS. Two kinds of information have been tested: descriptive (respondents are provided with the estimated travel times on each route), and prescriptive (respondents are provided with the estimated shortest route). For each kind of information four levels of accura…
Evolución de episodios pluviométricos en la Demarcación Hidrográfica del Júcar (1989-2016): del recurso al riesgo
2020
Este trabajo aborda la clasificación y evolución diacrónica de los episodios de lluvia (1989-2016) en ambientes mediterráneos, en la Demarcación Hidrográfica del Júcar. En base a datos del SAIH, y siguiendo criterios hidrológicos, se seleccionan 698 episodios, que se caracterizan con indicadores de precipitación acumulada, intensidad y persistencia. Mediante un análisis cluster se identifican tres tipologías (episodios de recurso limitado, de gran recurso a largo plazo y de riesgo) y se analiza su evolución temporal, estableciendo diferencias entre los episodios de interior y de litoral. Los resultados muestran una tendencia hacia el incremento del riesgo en detrimento del recurso en los tr…
Scour on alluvial bed downstream of grade-control structures
2004
This paper describes an approach for predicting local scour downstream of grade control structures. The developed analysis applies the incomplete self-similarity (ISS) theory for deducing some physically based dimensionless groups controlling the geometrical pattern of the scour profile. The scour measurements available in the literature in conjunction with numerous unpublished data allow a multiregressive calibration of the ISS relationships. The experimental sample includes different bed grain-size distributions and scales of the erosive phenomenon. The results prove that the ratio between the upstream water head and the weir height is able to explain the measurements of scour depth carri…
La Confederación fallida. Administración y usuarios en la cuenca del Turia (1928-1936)
2012
[EN] Between 1928 and 1936 the projects of river regulation in the Turia basin caused important conflicts. A private company, REVA, obtained a legal concession to build several reservoirs and hydropower stations. The traditional users rejected this initiative and promoted the creation of a basin authority, the Confederación Hidrográfica del Turia, in order to stop the private action, and to control the management of the river regulation. This article describes the different stages of this conflict, analyzing the position of all the involved agents, in order to improve our knowledge on a key period for the implementation of the Spanish basin authorities.
Zr, Hf and REE distribution in river water under different ionic strength conditions
2018
International audience; The Platani River flowing in south-central Sicily, interacting with evaporite rocks, generates a wide range of ionic strength in the water catchment from 0.1 to 5.0 mol kg−1. We sampled 38 river sites and analysed the composition for the dissolved fraction filtered through 0.45 μm, the truly dissolved fraction obtained through ultrafiltration (10 kDa) and the relative included colloidal fraction.This study was focused on the recognition of Zr, Hf and REE behaviour under changing ionic strength conditions, since this is one of parameters responsible for colloid stability in natural waters. In turn, this phenomenon leads to REE release from the colloidal fraction and t…
Gobio Genus Species Integrated Management System – Târnava Rivers Study Case (Transylvania, Romania)
2019
Abstract The lotic habitats quality indicative congeners species Gobio gobio, Gobio kessleri and Gobio albipinnatus populations’ dynamic in time (2004-2019) and space revealed a decreasing trend in these rivers ecological status. The ADONIS:CE tool has been used to build a backing management system model, based on these indicative fish species habitat needs, indicators for favourable conservation status, pressures and threats. This management system implementation in the field will favour the amelioration of lotic habitats and the ecological status recovering of two of the local fish species of conservative interest (G. kessleri and G. albipinnatus).
Flash-Floods Influence Macroinvertebrate Communities Distribution in Lotic Ecosystems
2019
Abstract Stream dwelling invertebrate populations are facing an ample array of stressors including the habitat imbalance caused by important floods. In this research we used a novel way to estimate the impact of floods upon the substrate, by utilising a remote variable named “flash-flood potential” (FFP), which accounts for the site slope and the average slope of the upstream catchment. The results showed that certain groups are sensitive to the influence of the FFP whereas other are not. We propose this remote variable as a surrogate for assessing stress imposed by floods and sediment scouring for lotic macroinvertebrates.
Species richness-standing crop relationship in stream bryophyte communities: patterns across multiple scales
2001
Summary 1 We tested for a unimodal (‘hump-backed’) relationship between species richness and standing crop at various spatial scales in stream bryophyte communities. Bryophyte species and their biomasses were determined from 20 to 25 quadrats in eight river and six stream sites in northern Finland. 2 Regression analyses revealed a quadratic relationship between richness and biomass in only two of the river sites and a positive correlation in one other. A quadratic relationship was detected in three stream sites and richness increased linearly with biomass in another. 3 We also tested for the hump-shaped pattern across individual stream boulders, representing an elevational gradient from con…